Production embroidering of textiles and the like is mostly carried out using computer controlled equipment having multiple work stations. During embroidering, a local portion of the fabric of a workpiece article is held taut in an embroidery hoop or the like. The hoop and thus the fabric is moved in the horizontal x-y plane within the throat of a work station of an embroidery machine. The work station comprises a sewing head positioned above and spaced apart from a needle plate and shuttled bobbin assembly. Each sewing head comprises a multiplicity of threaded needles which move up and down, one at a time, in the vertical z-plane, penetrating the fabric and interacting with the shuttled bobbins beneath the needle plate. The hoop with clamped in place fabric is typically attached to a motorized component, called a pantograph, which moves laterally in the x-y plane in a computer-controlled manner, to move the captured fabric beneath the sewing head. Thus, through coordinated action of the sewing head, bobbins, and pantograph, the desired thread pattern which comprises the embroidery is created. Typically the embroidery equipment comprises multiple work stations, side by side, with each head having multiple sewing needles.
It is common that almost finished articles are embroidered with localized decorative designs. Shirts, caps, belts, tablecloths are typical articles which are embroidered. Thus, it is important that the embroidery be satisfactorily done since the articles have relatively high value at the time they are processed.
However embroidery is done, any flexible cloth or other article is almost always gripped within an embroidery hoop, as described. A hoop typically comprises two pieces, an outer ring and an inner ring, usually round, oval or almost rectangular oblong. One ring is smaller than the other; and, when they are engaged the fabric is captured within the space between the outside of the inner ring and the inside of the outer ring, so that the fabric is stretched across the span of the inner ring.
In production using computerized machines, the position and orientation of the embroidery on the article is a function of how the article is captured within the hoop (or how the article is "hooped"), and how the hoop is oriented with respect to the pantograph of the machine. Typically, there is a means for attaching and detaching a hoop to and from the pantograph in a relatively precise manner. Thus, the position and orientation of the embroidery on an article is largely a function of how the fabric of the article is captured within the hoop. The productivity of a particular machine is largely dependent on how rapidly the operator can properly hoop an article outside of the machine, remove an embroidered article from the machine, and install the next hooped article in the machine, with minimum of machine rest time. Obviously, if an operator is attending to a machine with multiple heads and the embroidering is fast, this can create a lot of work. In practice, it is a problem that articles are not placed in the machine sufficiently accurately or rapidly. Once the article is hooped, in a typical present day process, there is no means for adjusting the orientation within the x-y planes. Thus, it is ordinary that a separate hooping table will be employed, and various guides, gages and rulers are used in time consuming ways to attempt to properly orient the article within the hoop.
Another kind of problem arises when a multilayered article is embroidered; as for example, when the pocket of a shirt is being embroidered. If the pocket location of the shirt is captured in the hoop, the main layer of the body of the shirt will lie very close to the outer layer which comprises the pocket. Obviously, the embroidering needles will penetrate both layers of fabric, thereby compromising the function of the pocket in the finished shirt. Similar problems arise for purses, bags and certain tubular items. There has been no good solution to this problem in the past. One poor alternative is to embroider the outer layer of the pocket prior to full attachment to the inner layer, or main body of the article. For already finished shirts with pockets, the process requires manually removing the stitches to separate the top layer of the pocket, embroidering on it, and restitching to form the pocket.